drivers/media/video/usbvision/usbvision-i2c.c

   1 /*
   2  * usbvision_i2c.c
   3  *  i2c algorithm for USB-I2C Bridges
   4  *
   5  * Copyright (c) 1999-2007 Joerg Heckenbach <joerg@heckenbach-aw.de>
   6  *                         Dwaine Garden <dwainegarden@rogers.com>
   7  *
   8  * This module is part of usbvision driver project.
   9  * Updates to driver completed by Dwaine P. Garden
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24  */
  25
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/delay.h>
  30 #include <linux/slab.h>
  31 #include <linux/version.h>
  32 #include <linux/utsname.h>
  33 #include <linux/init.h>
  34 #include <asm/uaccess.h>
  35 #include <linux/ioport.h>
  36 #include <linux/errno.h>
  37 #include <linux/usb.h>
  38 #include <linux/i2c.h>
  39 #include "usbvision.h"
  40
  41 #define DBG_I2C         1<<0
  42
  43 static int i2c_debug = 0;
  44
  45 module_param (i2c_debug, int, 0644);                    // debug_i2c_usb mode of the device driver
  46 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  47
  48 #define PDEBUG(level, fmt, args...) \
  49                 if (i2c_debug & (level)) info("[%s:%d] " fmt, __PRETTY_FUNCTION__, __LINE__ , ## args)
  50
  51 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
  52                             short len);
  53 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
  54                            short len);
  55
  56 static inline int try_write_address(struct i2c_adapter *i2c_adap,
  57                                     unsigned char addr, int retries)
  58 {
  59         struct usb_usbvision *usbvision;
  60         int i, ret = -1;
  61         char buf[4];
  62
  63         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
  64         buf[0] = 0x00;
  65         for (i = 0; i <= retries; i++) {
  66                 ret = (usbvision_i2c_write(usbvision, addr, buf, 1));
  67                 if (ret == 1)
  68                         break;  /* success! */
  69                 udelay(5);
  70                 if (i == retries)       /* no success */
  71                         break;
  72                 udelay(10);
  73         }
  74         if (i) {
  75                 PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr);
  76                 PDEBUG(DBG_I2C,"Maybe there's no device at this address");
  77         }
  78         return ret;
  79 }
  80
  81 static inline int try_read_address(struct i2c_adapter *i2c_adap,
  82                                    unsigned char addr, int retries)
  83 {
  84         struct usb_usbvision *usbvision;
  85         int i, ret = -1;
  86         char buf[4];
  87
  88         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
  89         for (i = 0; i <= retries; i++) {
  90                 ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
  91                 if (ret == 1)
  92                         break;  /* success! */
  93                 udelay(5);
  94                 if (i == retries)       /* no success */
  95                         break;
  96                 udelay(10);
  97         }
  98         if (i) {
  99                 PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr);
 100                 PDEBUG(DBG_I2C,"Maybe there's no device at this address");
 101         }
 102         return ret;
 103 }
 104
 105 static inline int usb_find_address(struct i2c_adapter *i2c_adap,
 106                                    struct i2c_msg *msg, int retries,
 107                                    unsigned char *add)
 108 {
 109         unsigned short flags = msg->flags;
 110
 111         unsigned char addr;
 112         int ret;
 113         if ((flags & I2C_M_TEN)) {
 114                 /* a ten bit address */
 115                 addr = 0xf0 | ((msg->addr >> 7) & 0x03);
 116                 /* try extended address code... */
 117                 ret = try_write_address(i2c_adap, addr, retries);
 118                 if (ret != 1) {
 119                         err("died at extended address code, while writing");
 120                         return -EREMOTEIO;
 121                 }
 122                 add[0] = addr;
 123                 if (flags & I2C_M_RD) {
 124                         /* okay, now switch into reading mode */
 125                         addr |= 0x01;
 126                         ret = try_read_address(i2c_adap, addr, retries);
 127                         if (ret != 1) {
 128                                 err("died at extended address code, while reading");
 129                                 return -EREMOTEIO;
 130                         }
 131                 }
 132
 133         } else {                /* normal 7bit address  */
 134                 addr = (msg->addr << 1);
 135                 if (flags & I2C_M_RD)
 136                         addr |= 1;
 137
 138                 add[0] = addr;
 139                 if (flags & I2C_M_RD)
 140                         ret = try_read_address(i2c_adap, addr, retries);
 141                 else
 142                         ret = try_write_address(i2c_adap, addr, retries);
 143
 144                 if (ret != 1) {
 145                         return -EREMOTEIO;
 146                 }
 147         }
 148         return 0;
 149 }
 150
 151 static int
 152 usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
 153 {
 154         struct i2c_msg *pmsg;
 155         struct usb_usbvision *usbvision;
 156         int i, ret;
 157         unsigned char addr;
 158
 159         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
 160
 161         for (i = 0; i < num; i++) {
 162                 pmsg = &msgs[i];
 163                 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
 164                 if (ret != 0) {
 165                         PDEBUG(DBG_I2C,"got NAK from device, message #%d", i);
 166                         return (ret < 0) ? ret : -EREMOTEIO;
 167                 }
 168
 169                 if (pmsg->flags & I2C_M_RD) {
 170                         /* read bytes into buffer */
 171                         ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
 172                         if (ret < pmsg->len) {
 173                                 return (ret < 0) ? ret : -EREMOTEIO;
 174                         }
 175                 } else {
 176                         /* write bytes from buffer */
 177                         ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
 178                         if (ret < pmsg->len) {
 179                                 return (ret < 0) ? ret : -EREMOTEIO;
 180                         }
 181                 }
 182         }
 183         return num;
 184 }
 185
 186 static int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
 187 {
 188         return 0;
 189 }
 190
 191 static u32 functionality(struct i2c_adapter *adap)
 192 {
 193         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
 194 }
 195
 196
 197 /* -----exported algorithm data: -------------------------------------  */
 198
 199 static struct i2c_algorithm usbvision_algo = {
 200         .master_xfer   = usbvision_i2c_xfer,
 201         .smbus_xfer    = NULL,
 202         .algo_control  = algo_control,
 203         .functionality = functionality,
 204 };
 205
 206
 207 /*
 208  * registering functions to load algorithms at runtime
 209  */
 210 static int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
 211 {
 212         PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
 213         PDEBUG(DBG_I2C, "ALGO   debugging is enabled [i2c]");
 214
 215         /* register new adapter to i2c module... */
 216
 217         adap->algo = &usbvision_algo;
 218
 219         adap->timeout = 100;    /* default values, should       */
 220         adap->retries = 3;      /* be replaced by defines       */
 221
 222         i2c_add_adapter(adap);
 223
 224         PDEBUG(DBG_I2C,"i2c bus for %s registered", adap->name);
 225
 226         return 0;
 227 }
 228
 229 /* ----------------------------------------------------------------------- */
 230 /* usbvision specific I2C functions                                        */
 231 /* ----------------------------------------------------------------------- */
 232 static struct i2c_adapter i2c_adap_template;
 233 static struct i2c_client i2c_client_template;
 234
 235 int usbvision_i2c_register(struct usb_usbvision *usbvision)
 236 {
 237         memcpy(&usbvision->i2c_adap, &i2c_adap_template,
 238                sizeof(struct i2c_adapter));
 239         memcpy(&usbvision->i2c_client, &i2c_client_template,
 240                sizeof(struct i2c_client));
 241
 242         sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
 243                 " #%d", usbvision->vdev->minor & 0x1f);
 244         PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
 245         usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
 246
 247         i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
 248         i2c_set_clientdata(&usbvision->i2c_client, usbvision);
 249
 250         usbvision->i2c_client.adapter = &usbvision->i2c_adap;
 251
 252         if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
 253                 printk(KERN_ERR "usbvision_register: can't write reg\n");
 254                 return -EBUSY;
 255         }
 256
 257 #ifdef CONFIG_MODULES
 258         /* Request the load of the i2c modules we need */
 259         switch (usbvision_device_data[usbvision->DevModel].Codec) {
 260         case CODEC_SAA7113:
 261                 request_module("saa7115");
 262                 break;
 263         case CODEC_SAA7111:
 264                 request_module("saa7115");
 265                 break;
 266         }
 267         if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
 268                 request_module("tuner");
 269         }
 270 #endif
 271
 272         return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
 273 }
 274
 275 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
 276 {
 277
 278         i2c_del_adapter(&(usbvision->i2c_adap));
 279
 280         PDEBUG(DBG_I2C,"i2c bus for %s unregistered", usbvision->i2c_adap.name);
 281
 282         return 0;
 283 }
 284
 285 void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
 286                       void *arg)
 287 {
 288         i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
 289 }
 290
 291 static int attach_inform(struct i2c_client *client)
 292 {
 293         struct usb_usbvision *usbvision;
 294
 295         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 296
 297         switch (client->addr << 1) {
 298                 case 0x42 << 1:
 299                 case 0x43 << 1:
 300                 case 0x4a << 1:
 301                 case 0x4b << 1:
 302                         PDEBUG(DBG_I2C,"attach_inform: tda9887 detected.");
 303                         break;
 304                 case 0x42:
 305                         PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
 306                         break;
 307                 case 0x4a:
 308                         PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
 309                         break;
 310                 case 0x48:
 311                         PDEBUG(DBG_I2C,"attach_inform: saa7111 detected.");
 312                         break;
 313                 case 0xa0:
 314                         PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
 315                         break;
 316
 317                 default:
 318                         {
 319                                 struct tuner_setup tun_setup;
 320
 321                                 PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
 322                                 usbvision->tuner_addr = client->addr;
 323
 324                                 if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
 325                                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 326                                         tun_setup.type = usbvision->tuner_type;
 327                                         tun_setup.addr = usbvision->tuner_addr;
 328                                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 329                                 }
 330                         }
 331                         break;
 332         }
 333         return 0;
 334 }
 335
 336 static int detach_inform(struct i2c_client *client)
 337 {
 338         struct usb_usbvision *usbvision;
 339
 340         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 341
 342         PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
 343         return 0;
 344 }
 345
 346 static int
 347 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
 348                      char *buf, short len)
 349 {
 350         int rc, retries;
 351
 352         for (retries = 5;;) {
 353                 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
 354                 if (rc < 0)
 355                         return rc;
 356
 357                 /* Initiate byte read cycle                    */
 358                 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
 359                 /*                    d3 0=Wr 1=Rd             */
 360                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 361                                       (len & 0x07) | 0x18);
 362                 if (rc < 0)
 363                         return rc;
 364
 365                 /* Test for Busy and ACK */
 366                 do {
 367                         /* USBVISION_SER_CONT -> d4 == 0 busy */
 368                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 369                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 370                 if (rc < 0)
 371                         return rc;
 372
 373                 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
 374                 if ((rc & 0x20) == 0)   /* Ack? */
 375                         break;
 376
 377                 /* I2C abort */
 378                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 379                 if (rc < 0)
 380                         return rc;
 381
 382                 if (--retries < 0)
 383                         return -1;
 384         }
 385
 386         switch (len) {
 387         case 4:
 388                 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
 389         case 3:
 390                 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
 391         case 2:
 392                 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
 393         case 1:
 394                 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
 395                 break;
 396         default:
 397                 printk(KERN_ERR
 398                        "usbvision_i2c_read_max4: buffer length > 4\n");
 399         }
 400
 401         if (i2c_debug & DBG_I2C) {
 402                 int idx;
 403                 for (idx = 0; idx < len; idx++) {
 404                         PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
 405                 }
 406         }
 407         return len;
 408 }
 409
 410
 411 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
 412                                  unsigned char addr, const char *buf,
 413                                  short len)
 414 {
 415         int rc, retries;
 416         int i;
 417         unsigned char value[6];
 418         unsigned char ser_cont;
 419
 420         ser_cont = (len & 0x07) | 0x10;
 421
 422         value[0] = addr;
 423         value[1] = ser_cont;
 424         for (i = 0; i < len; i++)
 425                 value[i + 2] = buf[i];
 426
 427         for (retries = 5;;) {
 428                 rc = usb_control_msg(usbvision->dev,
 429                                      usb_sndctrlpipe(usbvision->dev, 1),
 430                                      USBVISION_OP_CODE,
 431                                      USB_DIR_OUT | USB_TYPE_VENDOR |
 432                                      USB_RECIP_ENDPOINT, 0,
 433                                      (__u16) USBVISION_SER_ADRS, value,
 434                                      len + 2, HZ);
 435
 436                 if (rc < 0)
 437                         return rc;
 438
 439                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 440                                       (len & 0x07) | 0x10);
 441                 if (rc < 0)
 442                         return rc;
 443
 444                 /* Test for Busy and ACK */
 445                 do {
 446                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 447                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 448                 if (rc < 0)
 449                         return rc;
 450
 451                 if ((rc & 0x20) == 0)   /* Ack? */
 452                         break;
 453
 454                 /* I2C abort */
 455                 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 456
 457                 if (--retries < 0)
 458                         return -1;
 459
 460         }
 461
 462         if (i2c_debug & DBG_I2C) {
 463                 int idx;
 464                 for (idx = 0; idx < len; idx++) {
 465                         PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
 466                 }
 467         }
 468         return len;
 469 }
 470
 471 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 472                             short len)
 473 {
 474         char *bufPtr = buf;
 475         int retval;
 476         int wrcount = 0;
 477         int count;
 478         int maxLen = 4;
 479
 480         while (len > 0) {
 481                 count = (len > maxLen) ? maxLen : len;
 482                 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
 483                 if (retval > 0) {
 484                         len -= count;
 485                         bufPtr += count;
 486                         wrcount += count;
 487                 } else
 488                         return (retval < 0) ? retval : -EFAULT;
 489         }
 490         return wrcount;
 491 }
 492
 493 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 494                            short len)
 495 {
 496         char temp[4];
 497         int retval, i;
 498         int rdcount = 0;
 499         int count;
 500
 501         while (len > 0) {
 502                 count = (len > 3) ? 4 : len;
 503                 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
 504                 if (retval > 0) {
 505                         for (i = 0; i < len; i++)
 506                                 buf[rdcount + i] = temp[i];
 507                         len -= count;
 508                         rdcount += count;
 509                 } else
 510                         return (retval < 0) ? retval : -EFAULT;
 511         }
 512         return rdcount;
 513 }
 514
 515 static struct i2c_adapter i2c_adap_template = {
 516         .owner = THIS_MODULE,
 517         .name              = "usbvision",
 518         .id                = I2C_HW_B_BT848, /* FIXME */
 519         .client_register   = attach_inform,
 520         .client_unregister = detach_inform,
 521 #ifdef I2C_ADAP_CLASS_TV_ANALOG
 522         .class             = I2C_ADAP_CLASS_TV_ANALOG,
 523 #else
 524         .class             = I2C_CLASS_TV_ANALOG,
 525 #endif
 526 };
 527
 528 static struct i2c_client i2c_client_template = {
 529         .name           = "usbvision internal",
 530 };
 531
 532 /*
 533  * Overrides for Emacs so that we follow Linus's tabbing style.
 534  * ---------------------------------------------------------------------------
 535  * Local variables:
 536  * c-basic-offset: 8
 537  * End:
 538  */